George Brainard tests blue light on astronauts’ body clocks

Neuroscientist George Brainard is investigating the use of different kinds of light to enhance astronauts’ sleep – and to boost their waking performance.

George Brainard is a neuroscientist working with the National Space Biomedical Research Institute. He’s testing how light affects astronauts working and sleeping in space.

George Brainard: An astronaut here on Earth experiences a 24 hour day/night cycle just like you and I. Now when they’re on the space station, they’re circling the planet every 90 minutes. So they’ve gone from a 24 hour day to a 90 minute day.

Your circadian rhythm is what tells you when it’s time to sleep and wake up. It’s tied to light – in particular, the blue-indigo region of the spectrum, according to Brainard.

George Brainard: And that’s the opportunity that we’re working on. Can you blue-enrich white-appearing light and get a strong circadian stimulus for the astronauts, and will this in fact help their sleep?

Dr. Brainard is also testing to see if a pure form of blue light will boost the waking performance of astronauts.

George Brainard: So for example, if an astronaut is wakened up out of sleep and there has to be a spacewalk for emergency purposes, you want that astronaut at their peak alertness.